Instrument for testing the roundness of the inner wall of a pipe or other hollow cylinder

Description

FIG. 1 is a top view of the apparatus of the present invention;

FIG. 2 is a right view thereof, the left side view being a mirror image thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a rear view thereof, with the valve closed;

FIG. 5 is a rear view thereof, with the valve open;

FIG. 6 is a front view thereof, with the valve closed;

FIG. 7 is a front view thereof, with the valve open;

FIG. 8 is a rear perspective view thereof;

FIG. 9 is a side perspective view thereof; and,

FIG. 10 is a side exploded view thereof.

The broken lines shown represent environmental subject matter and form no part of the claimed design.

Claims

The ornamental design for an instrument for testing the roundness of the inner wall of a pipe or other hollow cylinder, as shown and described.